By Dr Ananya Mandal, MD
Heparin is a widely used injectable anticoagulant that is used to break down blood clots. It is a highly-sulfated glycosaminoglycan and the most highly negatively charged biological molecule known to mankind. It is also used to create an anticlotting surface inside various medical devices such as renal dialysis machines and test tubes.
Anticoagulants work by decreasing the clotting ability of the blood, helping to prevent the formation of clots as well as stopping the further expansion of any existing clots. Although heparin does not break down existing blood clots, it does enhance the body’s natural mechanism involved in clot lysis.
Source of heparin
Pharmaceutical-grade heparin is derived from the mucosal tissue of animals that have been slaughtered for meat such as pigs and cattle. Research conducted between 2003 and 2008 eventually led to the synthetic development of low molecular weight heparins in 2011.
Role of heparin in the body
Heparin is a naturally occurring anticoagulant. However, its actual physiological role in the body is unclear and it has been suggested that its main purpose is defence against bacteria and other invading bodies, rather than anticoagulation.
The blood anticoagulation is mainly achieved through heparan sulfate proteoglycans found in endothelial cells. Heparin is contained in mast cells and is released into blood vessels only at sites of tissue injury to prevent blood clots forming. Heparin is found across various different animal species including invertebrates that do not have a coagulation system similar to that found in humans.
Reviewed by Sally Robertson, BSc
Last Updated: Aug 12, 2014